This application claims the benefit of the Korean Patent Application Nos. 10-2004-0113241, filed on Dec. 27, 2004, which is hereby incorporated by reference herein in their entirety.
1. Field of the Invention
The present invention relates to a digital rights management.
2. Description of the Related Art
In order to manage the use of digital contents, a digital rights management (DRM) has been developed. The use of the digital contents is protected using the DRAM technology. The use of the digital contents means available number and combination of the digital contents, whether to allow duplication (movement) of the digital contents, and number of allowable duplication (movement), as well as the storing, copying, moving and playing the digital contents.
The DRM has been developed for securing safe distribution of the digital contents and prevent illegitimate use, copy and distribution. Also, the DRM technology has been developed for protecting on-line contents of the commercially available products that are rapidly increased due to the wide-range use of file exchange programs between users. Although the on-line products are protected by the copyright law, it is practically difficult to regulate the illegitimate use of the contents and the offenders. Therefore, the DRM technology is based on the encoding of contents so as to prevent the illegitimate use of the contents.
FIG. 1 is a view illustrating a digital contents service and digital rights management method in a related art mobile terminal.
A contents provider encodes in advance the contents in an appropriate way for the purpose of DRM and registers them in a content server 10 (S10). The user accesses the corresponding contents server 10 through a mobile terminal 20, and downloads desired contents (S20). The contents downloaded in the mobile terminal 20 are decoded according to a user's replaying request and then are replayed (S30).
The related art digital contents service method has to manage the original digital contents that are not encodes together with the previously encoded digital contents. Since the digital contents that are encoded together with the original digital contents have to be managed in the contents provider and contents server together, a burden of a system for the digital rights management increases.
The related art DRM technology is dependent on the digital contents and is not dependent on the user's authenticity. For example, even though the DRM is locked with respect to the digital contents and a first terminal legitimately acquires the digital contents, if the contents are copied or moved from the first terminal to a second terminal without permission, there is a strong probability that the second terminal will use the digital contents without any disturbance. This is because the DRM is dependent on the digital contents. That is, strictly speaking, since the DRM is not dependent on the user, it is practically difficult to recognize the fact that the user (terminal) is changed.
That is, the related art digital rights management technology has the following drawbacks. Since the related art digital contents service method uses the same encryption key with respect to the same contents, if the digital contents downloaded to the user terminal are copied/moved to other terminals to which the use of the digital contents are not permitted, the copied/moved digital contents can be decoded in other terminals by the encryption key. Consequently, the illegitimate use of the digital contents is possible.